In magnetic resonance facilities very powerful magnetic fields are generated, usually by way of a superconducting basic field magnet. Accordingly known magnetic resonance facilities usually have very high specified power ratings, for example around 110 kW. The problem arises of being able to ensure such possible overall power consumption at all times, which is problematic with less well constructed power networks, as such power levels cannot or cannot always be supplied.
The significant power requirement of a magnetic resonance facility having a superconducting coil as its basic field magnet is largely determined here by a series of components of the magnetic resonance facility, for example the cold head of the cooling facility of the basic field magnet, which cools the liquid helium, the cooling facility for the remainder of the system, the gradient amplifier and the high-frequency amplifier. Each of these components must in some instances supply power levels exceeding 10 kW.
One problem here is the high power requirement of the magnetic resonance facility when using emergency power units, since, in order to be able to operate the magnetic resonance facility using the emergency power unit in an emergency, according to the current prior art the power of emergency power unit has to be matched to the theoretical maximum power consumption of the magnetic resonance facility, which is however not achieved in some instances during (rare) operation with emergency power.
To resolve such problems relating to the high power consumption of the magnetic resonance facility, it has been proposed that the power consumption of individual components should be reduced. Provision can thus be made to use regulatable compressors for the cold head or to use efficient coolers, so that it is possible to operate temporarily without compression for example at low ambient temperatures. Alternatively provision can be made for using components with lower power consumption, but these results in an unwanted lower system power. It is also conceivable to use a permanent magnet instead of a superconducting coil, so that the cooling outlay for the superconductor is no longer required but this makes the magnetic resonance facility very heavy and only permits very low field strengths.